异步接口中间过程的监听

异步接口与同步接口不同的是方法的返回值，一般来说，返回的对象是[backcolor=transparent]BaseTransfer，用户可通过[backcolor=transparent]ProgressListener监听进度，[backcolor=transparent]SpeedListener监听速度，通过 start开始任务， stop停止任务，而 waitUntilFinished将会阻塞直至任务完成， getResult可获取上传或下载结果。具体使用请参考本节的示例。
[backcolor=transparent]ProgressListener、[backcolor=transparent]SpeedListener和[backcolor=transparent]JobStatusListener分别为进度、速度、任务状态，各个的每个接口含义见下文的例子，而[backcolor=transparent]ProgressListenerAdapter、[backcolor=transparent]SpeedListenerAdapter和[backcolor=transparent]JobStatusListenerAdapter分别实现了以上接口，出错时默认会自动重试3次。特别注意的是，部分接口的调用是在IO线程中，在中执行费时的操作将有可能导致网络连接出错甚至中断。

以上传为例ServiceCredentials credentials = new ServiceCredentials(
    DemoConstants.ACCESS_ID,
    DemoConstants.ACCESS_KEY);

// 通过工厂类获得archiveManager接口
ArchiveManager archiveManager = OASFactory.archiveManagerFactory(credentials);
File file = new File("[pathToYourFile]");

final BaseTransfer<UploadResult> bt = archiveManager.uploadAsync(
    "[yourVaultName]", file);

//设置最大并发数，默认为3，最大为10
bt.setNumConcurrence(5);

bt.addProgressListener(new ProgressListener() {

    @Override
    public void onStart(String id) {
        // 任务开始时调用，其中id为Multipart Upload任务ID，对于一般上传任务id为空
        System.out.println("Start! Upload ID: " + id);
    }

    @Override
    public boolean onError(Range range, Throwable t) {
        // 出错时调用，range是出错的字节范围，t是相应的错误
        // 当返回true时，BaseTransfer会进行重试，false则放弃
        System.out.println("ERROR!!!");
        return false;
    }

    @Override
    public void onCompleted() {
        // 任务完成时调用
        System.out.println("Upload complete");
    }

    @Override
    public void onProgressed(long current, long total) {
        // 上传进度，total为文件字节大小，current为当前已上传字节数
        System.out.println("Progress: " + current + " / " + total);
    }
});

bt.start();

final Timer timer = new Timer();
timer.scheduleAtFixedRate(new TimerTask() {

    @Override
    public void run() {
        System.out.println("Running time: " + bt.getRunningTime() + " seconds");
        System.out.println("Completed size: " + bt.getSizeCompleted() + " bytes");
        System.out.println("Total size: " + bt.getSizeTotal() + " bytes");
        System.out.println("Average speed: " + bt.getAverageSpeedInBytesPerSecond()
                           + " B/s");
        if (bt.isComplete()) {
            timer.cancel();
            synchronized (bt) {
                bt.notify();
            }
        }
    }

}, 0, 1000);

synchronized (bt) {
    try {
        bt.wait();
    } catch (InterruptedException e) {
        logger.error("", e);
    }
}

// 任务结束
System.out.println("=============================");
System.out.println("Running time: " + bt.getRunningTime() + " seconds");
System.out.println("Completed size: " + bt.getSizeCompleted() + " bytes");
System.out.println("Total size: " + bt.getSizeTotal() + " bytes");
System.out.println("Average speed: " + bt.getAverageSpeedInBytesPerSecond() + " B/s");
UploadResult uploadResult = bt.getResult();
System.out.println("Archive ID: " + uploadResult.getArchiveId());
System.out.println("ContentEtag: " + uploadResult.getContentEtag());